Dyestuff intermediate from halogen benzoyl-benzoic acids



Patented Oct. 21, 1930 UNITED STATES PATENT oF IC 1 JOHN THOMAS AND noon ALEERT'EDWARD DREs'cHEn, E GRANGEMQ TH', scoTLAnn, nssmuons T0 SCOTTISH nYEs, LIMITED, 01 GRANGEMOUTH, STIRLING, SCOTLAND 1 nYEs'ruFE INTERMEDIATE FROM HALOGEN EuzoY -EENzom ACIDS This invention relates to the production of dyestufl intermediates from halogen benzoyl benzoic acids.

In the nomenclature of the benzoyl benzoic acids given below the positions in the benzene nucleus containing the carboxyl group are labelled from 1 to 6 beginning with thecarboxyl group, whilst the positions in the benzene nucleus of the benzoyl group are labelled 1 to 6 beginning with the carbonyl group.

Compounds such as sodium sulphite appear to have diflerent action on different l1alogen-Q-benzoyl-benzoic acids when treated in the same way, for example although (3- nitro 4:- halogen) 2 benzoyl benzoic acids will react withsodium sulphite to give the sulphonic acid salts, if the conversion of -halogen) -2-benzoyl-benzoic*acid is attempted in a similar way no appreciable quantity of the equivalent 1-sulpho)-2- benzoyl-benzoic acid'is formed.

The object of the present invention is to provide a process for the production of dyestufi" intermediates by the reaction of a sulphite or hydrogen-sulphite on halogen-Z-benzoyl-benzoic acids generally and particularly (4'-halogen)-2-benzoyl-benzoic acid.

To this end We have made a number of experiments and have found that by treating the salts of the halogen-Q-benzoyl-benzoic acid with a sulphite or bisulphite at a temperature higher than about 100 C., the desired results are obtained.

The invention consists in reacting 'on halogen-2benzoyl-benzoic acids except (3- nitro 4' halogen) -2 benzoyl -benzoic acids with a sulphite or sulphites of sodium or the like at a temperature higher than about 100 C. especially by reacting on (F-halogen) -2- benzoyl-benzoic acid with neutral alkaline sulphite solution under the conditions indicated above.

' ample with sulphuric acid, into 7 solution.

No Drawing." Application filed December 7, 1926, Serial 11 153,214, and in Great Britain December 24, 1525.

I .Ewample 1 I 282 partsof thesodium' salt of (4'-chlor)- Q-benzoyl-benzoic acid and 189 parts of sodifor example 6 to 24'hours after which the 'contents of the vessel are allowed to cool. The

then filtered to remove any unchanged (1- 'chlor)-2-benzoyl-benzoic. acid that may be present,-the liquors are treated so as to isolate the (4-sulpho) -2-benzol-benzoic acid. The product may be separated in the form of the sodium salt by evaporation or in the form of the acid by salting out after addition of mineral acid. i

, Ewample 2 The (4.-sul ho)-2-benzol-benzoic acid can be convertedv y condensing agents, for: exthe anthraquinone sulphonic acid.

This process may b ."carried out as follows 20 grams of the dry product as obtained by V the evaporation of the liquors in the above example, which contain also sodium chloride, sodium sulphate, and possibly sodium sulphite, -is.added to 140 grams of 5 per cent. oleum with stirring at 90 C; The temperature isthen raised to 180 C. and maintainedat that temperature for 15 minutes. The melt is then cooled and poured into 1250 cc. of water.

This mixture is boiled and filtered hot to remove traces of. 2-chlonanthraquinone.

The filtrates are salted out by adding sufficient sodium chloride tomake a 5 per cent. salt The mixture is boiled andallowed g t I General I In place of sodium or sodium hydrogen sulphite similar compounds of potassium or the like may be employed.

The reaction indicated between (Q-halogen) -2-benzoyl-benzoic acid and the reacting compound is of commercial importance among other reasons oecause it enables anthraquinoneQ-sulphonic acid to be prepared without the formation of isomeric bodies as by-products.

The reaction indicated proceeds smoothly and the sulpho-benzoyl-benZoic acids are easily obtained in a state of purity and readily separated from any unchanged halogen- 2-benzoyl-benzoic acid that may be present.

The addition of a small proportion of a copper salt appears to be beneficial; for instance, in Example 1, 3 parts of copper sulphate may with advantage be added.

The invention is not confined to halogen benzoyl-loenzoic acids in which. the halogen is attached to the benzene nucleus not contain ing the carboxylic acid substituent, but can be applied to halogen-2-benzoyl-benzoic acids and their derivatives generally, including those containing halogen in the benzene nucleus to which is attached also the carboxylic acid substituent such as, for example, those halogenated benzoyl-ortho -benzoic acids which are made by condensing halogenated phthalic ai'ihydride with benzene and its derivatives.

To state the matter in other terms the invention is applicable to halogen derivatives of Q-benzoyl-l'ienzoic acid no matter in which of its two benzene nuceli the halogen or halogens may be present. Further, where relerence has been made to normal sulphite or acid sulphite the one is to include the other unless the context requires the contrary.

Having now describedour invention what We claim as new and desire to secure by Letters Patent is z 1. A process for producing dyestuft intermediates which consists in acting on (U-halogen)-2-benzoyl-benzoic acid with a solution of normal sodium sulphite at a temperatur of about 180 C.

2. A process for producing dycstuif intermediates which consists in acting on the sodium salt of (4-chlor)-2-benzoyl-benzoic acid with a solution of neutral sodium sulphite in a closed vessel at a temperature which causes the mixture or solution to have a pressure of from 100-12O lbs. per square inch.

3. 4- (sulpho) -2-benzoyl-benzoic acid.

4. A process for producing dyestufli' intermediates which consists in acting on (4U-halogen)-2-benzoy'l-benzoic acid with a water soluble sulphite in aqueous solution at an elevated temperature.

5. A process for producing dyestutf intermediates which consists in reacting on (halogen)-2-benzoyl-benzoic acids except (3 nitro i halogen) Q-benzoyl-benzoic acids with a water soluble sulphite in aqueous solution at a temperature above 100 C.

6. A process for producing dyestuii" inter mediates which consists in acting on halo- A a water .on at an ele- 

